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1.
Poblac. salud mesoam ; 19(2)jun. 2022.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1386957

RESUMO

Resumen Introducción: el laboratorio de citogenética del Instituto de Investigaciones en Salud (INISA) de la Universidad de Costa Rica estableció un Servicio de Dosimetría Biológica en enero del 2020 utilizando biomarcadores citogenéticos de exposición a radiaciones ionizantes. Es el primero de su tipo en la región centroamericana. Objetivo: establecer un servicio de dosimetría biológica para Costa Rica, elaborando una curva de calibración dosis-efecto para rayos gamma. Metodología: para la realización de la curva de calibración se irradiaron muestras de sangre periférica in vitro con rayos gamma de dos voluntarios, uno femenino y otro masculino, en 11 puntos de dosis en el rango de 0 a 5 Gy. Se cultivó la sangre acorde a los protocolos internacionales durante 48 horas y se registraron las aberraciones inducidas. Los programas Dose Estimate V5.2 y R versión 4.03 se utilizaron para el cálculo de los coeficientes de la curva de calibración que correlaciona la frecuencia de cromosomas dicéntricos con la dosis. Resultados: los coeficientes de la curva son α: 0.02737±0.00658, ß: 0,05938±0,00450 y C: 0.00129±0.00084. Estos coeficientes tienen valores similares a los reportados internacionalmente. La curva se validó calculando dos dosis incógnitas, en la primera incógnita la dosis suministrada fue de 1,5 Gy y la dosis estimada fue 1,47 Gy y en la segunda la dosis suministrada fue de 4 Gy y la dosis estimada fue 3,616 Gy, para ambos casos no existen diferencias estadísticamente significativas entre las dosis suministradas y las estimadas. Conclusiones: actualmente El Servicio de Dosimetría Biológica del INISA puede estimar dosis absorbida en personas que se sospecha de una sobre exposición a rayos gamma en personal ocupacionalmente expuesto o personas involucradas en un accidente radiológico.


Abstract Introduction. The cytogenetics laboratory of the Health Research Institute (INISA) of the University of Costa Rica established a Biological Dosimetry Service in January 2020 using cytogenetic biomarkers of exposure to ionizing radiation. It is the first of its kind in the Central American region. Objective: establish a biological dosimetry service for Costa Rica, developing a dose-effect calibration curve for gamma rays. Methodology: to carry out the calibration curve, peripheral blood samples from two volunteers, one female and the other male, were irradiated in vitro with gamma rays, at 11 dose points in the range of 0 to 5 Gy. Blood was cultured according to international protocols for 48 hours and induced aberrations were recorded. The Dose Estimate V5.2 and R version 4.03 programs were used to calculate the coefficients of the calibration curve that correlates the frequency of dicentric chromosomes with the dose. Results: the coefficients of the curve are α: 0.02737 ± 0.00658, ß: 0.05938 ± 0.00450 and C: 0.00129 ± 0.00084. These coefficients have values similar to those reported internationally. The curve was validated by calculating two unknown doses, in the first unknown case the delivered dose was 1.5 Gy and the estimated dose was 1.47 Gy and in the second case the delivered dose was 4 Gy and the estimated dose was 3.616 Gy. for both cases there are no statistically significant differences between the delivered and estimated doses. Conclusions: the Biological Dosimetry Service of the INISA can estimate absorbed dose in persons suspected of overexposure to gamma rays in occupationally exposed personnel or persons involved in a radiological accident.Health is loaded with symbolisms and practical manifestations that differ according to social groups and sociocultural contexts. In order to make everyday life and needs visible, the Theoretical Paradigm of Social Representations provides the theoretical-methodological bases necessary to understand the common sense knowledge associated with health among the Nicaraguan migrant population in Costa Rica. Methodology: Qualitative study with ethnographic approach that aimed to identify the social representation of health, through the process of objectification, present among Nicaraguan migrants living in Costa Rica. Data collected through semi-structured interviews, participant observation, and field diaries. Processing according to Content Analysis. Results: The social representation of health found behaves analogously to a formula; where, the search for peaceful environments is added to the achievement of financial stability to result in two interdependent representations: 1) Health as physical-mental strength; and 2) Health as a future and abstract sensation of well-being, happiness and transcendence. The socio-political antecedents in Nicaragua, the migratory process, and the adaptation to Costa Rica play a preponderant role in shaping the representation on health. Conclusion: Social representations about health have direct practical implications on the ways of life and needs of migrant groups. Understanding their common sense knowledge allows to move towards more contextualized public policies. More integration of the thoughts, opinions and feelings of migrants in decision-making platforms is recommended.


Assuntos
Humanos , Masculino , Feminino , Radiação Ionizante , Dosimetria , Costa Rica , Raios gama
2.
Chinese Journal of Cancer Biotherapy ; (6): 569-576, 2019.
Artigo em Chinês | WPRIM | ID: wpr-798336

RESUMO

@# Objection: To analyze the factors affecting the prognosis of patients with gastric neuroendocrine neoplasms (G-NENs) by using the surveillance of National Cancer Institute (NCI) of America, Epidemiology and End Results (SEER) database, and to construct a prognostic Nomogram model for individualized prediction of prognosis in patients with G-NENs. Methods: The clinical data of 2720 G-NENs patients with complete follow-up data from 2010 to 2015 in the SEER database were collected. The prognostic Nomogram model was constructed based on independent risk factors determined by survival analysis. The consistency index (C-index) and calibration curve were used to evaluate its accuracy.Area under the curve (AUC) was used to compare the evaluation value between the Nomogram and the 7th edition of AJCC TNM staging. Results: The 1-, 3-, and 5-year survival rates of 2,720 patients with G-NENs were 88.14%, 79.09%, and 71.86%, respectively. Multivariate COX regression analysis showed that gender, age, marital status, other associated tumors, histological type, tumor grade, T stage, M stage, and surgery were independent risk factors affecting survival time of GNENs patients. The C-index of newly constructed Nomogram prediction model was 0.816, which was significantly higher than 0.702 of the 7thAJCC TNM staging (P<0.001), and the 1-, 3- and 5-year calibration curves showed a good agreement between predicted survival and actual survival. The AUC for 1-, 3- and 5-year survival by Nomogram prognostic model was 0.800, 0.811, and 0.820, which was higher than 0.650, 0.688 and 0.698 of the 7th AJCC TNM staging, and the differences were statistically significant (Z= 6.600, 8.085, 9.632, all P<0.0001). Conclusion: The Nomogram prediction model drawn in this study has a high prognostic value and can individually predict the survival rate of G-NENs patients, which is helpful for clinical treatment decision-making and clinical research options.

3.
Artigo em Inglês | IMSEAR | ID: sea-150877

RESUMO

A simple, rapid, accurate, precise, and inexpensive method for the determination of citicoline has been developed using double beam UV spectrophotometer. Ultraviolet spectrophotometric analysis was carried out on a Shimadzu UV 1800 (Shimadzu, Japan) spectrophotometer, in a 1cm quartz cuvette. Citicoline has absorption maxima at 272 nm and the measurements were obtained against distilled water. Beer Lambert’s law was obeyed in the concentration range of 5-50μg/ml with correlation coefficient (r2) 0.9998. The analytical method was successfully validated in order to verify its proper selectivity, linearity, accuracy and precision for the goal intended and its further implementation for the quantification of the active compound in the pharmaceutical speciality for quality control.

4.
Chinese Journal of Laboratory Medicine ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-584056

RESUMO

Objective To study suitability of a series of lyophilized serum with definitive HBV DNA value in fluorescence quantitative COBAS Amplicor HBM kit and a sample with 106 copies/ml HBV DNA was prepared, and sent to various manufactures which would be asked to detect the samples using their own kits. Then a calibration curves from CT values of the series to the corresponding concentrations was compared with that obtained from the external standard-calibration curve with the manufactures series. Results The standard-calibration curve with the series of lyophilized serum showed an excellent correlation (

5.
Chinese Traditional Patent Medicine ; (12)1992.
Artigo em Chinês | WPRIM | ID: wpr-569154

RESUMO

Reversed high-pressure liquid chromatography was applied in content determination of bufogenin in Liuying Pills. The sample was extracted with chloroform. Using the calibration curve method of external peak area for quantitation, ODS as chromatographic column, 60% methanol as mobile phase, and detection wavelength at 298nm, the recovery reached 97.7%(CV=0.5%).

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